Abstract: In order to reduce the cost of denitrification of thermal power units under the condition of satisfying the environmental emission standards,a calculation model of the denitrification cost for electricity generation was established for the selective catalytic reduction(SCR)denitrification system of a 350MW coal-fired unit. The cost of denitrification is divided into two parts:fixed denitrification cost for electricity generation and variable denitrification cost for electricity generation. The fixed denitrification cost for electricity generation includes depreciation cost,accounting cost,catalyst replacement cost,overhaul cost,labor cost,compensation price and other cost. The variable denitrification cost for electricity generation includes cost of electricity,cost of ammonia injection and cost of sewage. Taking denitrification cost for electricity generation as the evaluation index,the optimization model of denitrification system was established by using support vector machine and particle swarm coupling algorithm,and the whole load section was optimized for denitration system. The results show that the prediction model can accurately predict the denitrification cost for electricity generation,and the maximum correlation coefficient is 99.9011%,which is in accordance with the actual operation of the power plant. The amount of ammonia spray required after the model optimization is reduced to 0.1578t/h,and the denitrification cost for electricity generation is significantly reduced. The system economy is improved,which can be used to guide the economic operation of the power plant.

Key words: selective catalytic reduction (SCR), denitrification cost for electricity generation, algorithm, optimize the operation

摘要： 为了在满足环保排放标准的条件下，降低火电机组脱硝成本，本文针对某350MW燃煤机组的选择性催化还原（SCR）脱硝系统，建立了度电脱硝成本的计算模型。该模型将脱硝成本分为固定成本和变动成本两部分，度电固定脱硝成本包括折旧成本、会计成本、催化剂更换成本、大修成本、人工成本、补偿电价、其他成本，度电变动脱硝成本包括电耗成本、喷氨成本、排污成本。以度电脱硝成本作为评价指标，利用支持向量机与粒子群耦合算法建立了脱硝系统运行优化模型，对脱硝系统进行了全负荷段优化。结果表明，预测模型能精确预测度电脱硝成本，最高相关系数可达99.9011%；经模型优化后，脱硝所需喷氨量降低至0.1578t/h，度电脱硝成本显著降低，系统经济性得到提高，可用于指导电厂经济运行。

关键词: 选择催化还原, 度电脱硝成本, 算法, 优化运行